Manicured nails - if your own are crap, acrylic are a good substitute
Er, trainers are allowed if trendy - I wear Diesel square toe ones with jeans - got 2 pairs, one white with green stripes and one cream with navy stripes.
Agree with skirts and fitted jackets.
ALWAYS wear make up (cannot fathom for one moment why people don't bother).
However, it doesn't really matter how trendy I look, the buggy with buggy board just blows the look for me!